Systems and methods for viewing medical images

ABSTRACT

For certain medical images, it is important and/or required that a user view all of a medical image at full resolution so that minute, but important, indicia in the medical image are not missed. A computing systems monitor the portions of the medical image that are displayed on the display device, notates those portions that have been displayed at full resolution (or other user-defined display parameters), and provides the user with information indicating portions that have not been viewed at full resolution and/or provides information indicating for which images of a multiple image examination full pixel display has been accomplished. The process reduces the possibility of missing an abnormality in a medical image due to the viewer not viewing a portion of the image at full resolution or using other user-defined display parameters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) to U.S.Provisional Application Ser. No. 60/625,690, filed on Nov. 4, 2004,which is hereby expressly incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to management and viewing of medical images and,more particularly, to systems and methods of tracking which portions ofmedical images have been displayed using predetermined displayparameters.

2. Description of the Related Art

Medical imaging is increasingly moving into the digital realm. Thisincludes imaging techniques that were traditionally analog, such asmammography, x-ray imaging, angiography, endoscopy, and pathology, whereinformation can now be acquired directly using digital sensors, or bydigitizing information that was acquired in analog form. In addition,many imaging modalities are inherently digital, such as MRI, CT, nuclearmedicine, and ultrasound. Increasingly these digital images are viewed,manipulated, and interpreted using computers and related computerequipment. Accordingly, there is a need for improved systems and methodsof viewing and manipulating these digital images.

SUMMARY OF THE INVENTION

A pixel is the smallest changeable element of a digital image, where animage comprises a plurality of pixels. For example, a mammographic imagemay include an array of 4,000 horizontal by 6,000 vertical pixels. Forall medical images, particularly for certain modalities such asmammography, for example, it is important that every image pixel isdisplayed on a display device and viewed by a viewer or reader, such asa doctor, nurse, or other medical staff member. For example, in thefield of mammography, diagnosis of a cancer may only be detectable in asmall number of pixels. Accordingly, if this small number of pixels isnot viewed by the viewer or reader, a misdiagnosis may be given to thepatient. If a mammography image comprises 16 million pixels (e.g., animage resolution of 4,000×4,000), all of the 16 million pixels cannot besimultaneously displayed on a display device with a resolution of2,048×1,536 (a 3.2 Megapixel display). Thus, only about ⅕ of the 16million pixels of the mammography image may be displayed simultaneouslyat full resolution on such a display device. In other words, if oneelects to display the image at full resolution, the entire 4,000×4,000pixel image cannot be simultaneously displayed on a 2,048×1,536 orsmaller matrix monitor. If one elects to display the complete area ofthe image, the only alternative is to display the entire image at areduced resolution, discarding a fraction of the pixels.

Because an entire medical image cannot be concurrently viewed at fullresolution on a typical display device, software applications currentlyallow viewing of portions of medical images at full resolution on thedisplay device. In some embodiments, a user may be required to adjustthe portion of the medical image that is displayed at full resolution onthe display device in an attempt to view all of the image pixels. Forexample, the viewer may select up to hundreds of portions of the imagefor sequential viewing at full resolution before the entire image hasbeen viewed at full resolution. As those of skill in the art willappreciate, manually tracking which portions of an image have beenviewed at full resolution is cumbersome and may not allow the viewer toaccurately determine when all relevant portions of the image have beenviewed at full resolution. Currently, there are no systems or methodsfor automatically tracking the portions of a medical image that havebeen displayed at full resolution, or for indicating those images forwhich all pixels have been presented on a display device at fullresolution. Accordingly, portions of medical images may not be viewed atfull resolution and important indicia in the medical image may beoverlooked. Thus, systems and methods for tracking portions of a medicalimage that have been viewed at full resolution are desired. Furthermore,systems and methods for allowing a viewer of the medical image tovisually distinguish those portions that have not been viewed at fullresolution are desired.

In one embodiment, the invention comprises a method of viewing medicalimages on a display device coupled to a computing system, wherein thedisplay device is configured to concurrently display N pixels of animage to a user. In one embodiment, the method comprises (a) receivingan image at the computing system, wherein the image comprises M pixels,wherein M is greater than N; (b) displaying on the display device aportion of the image comprising N pixels, wherein the image portion isdisplayed at full resolution; (c) determining whether each of the Mpixels of the image has been displayed on the display device, and (d) inresponse to determining that not all of the M pixels of the image havebeen displayed on the display device, returning to step (b).

In another embodiment, the invention comprises a method of viewing amammographic image in a viewing pane depicted on a display device,wherein the viewing pane is configured to display a predetermined numberof pixels. In one embodiment, the method comprises displaying themammographic image at a reduced resolution in the viewing pane,displaying a portion of the mammographic image at full resolution in theviewing pane, and displaying the mammography image at the reducedresolution in the viewing pane, wherein a portion of the reducedresolution image that corresponds with the portion of the mammographicimage that was displayed at full resolution is visually distinguishablefrom the remaining portion of the reduced resolution image.

In another embodiment, the invention comprises a computing system forviewing a mammographic image. In one embodiment, the system comprises adisplay device depicting a viewing pane, means for displaying a portionof the mammographic image at full resolution in the viewing pane, andmeans for displaying the entire mammographic image at the reducedresolution in the viewing pane, wherein the portion of the mammographicimage displayed at full resolution is visually distinguishable from theother portions of the reduced resolution mammographic image.

In another embodiment, the invention comprises a computing system forviewing a medical image. In one embodiment, the system comprises adisplay device having a predetermined number of pixels, an inputinterface configured to receive the medical image, an application modulecomprising software for initiating display of the medical image on thedisplay device, and a processing unit configured to execute thesoftware, wherein, in a first mode, the software initiates display ofthe entire medical image at a reduced resolution on the display device,in a second mode, the software initiates display of a portion of themedical image at full resolution on the display device, and, in a thirdmode, the software initiates display of the entire medical image at thereduced resolution on the display device, wherein a portion of thereduced resolution medical image corresponding to the portion of themedical image displayed at full resolution is visually distinguishablefrom the remaining portions of the reduced resolution medical image.

In another embodiment, the invention comprises a method of viewingmedical images. In one embodiment, the method comprises selectivelyviewing portions of a high resolution image and verifying that theentire high resolution image has been viewed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an exemplary computing system incommunication with a network and various networked devices.

FIG. 2 is a flowchart illustrating a method of tracking which portionsof a medical image have been displayed at full resolution.

FIG. 3 is a mammographic image, wherein the entire medical image isdisplayed at a reduced resolution.

FIG. 4 is the mammographic image of FIG. 3, wherein a portion of themammographic image is displayed at full resolution.

FIG. 5 is the mammographic image of FIG. 3, wherein portions of theimage that have been displayed at full resolution are color inverted.

FIG. 6 is an exemplary mammographic image, wherein a portion of theimage has been selected for display at full resolution and anotherportion of the image has already been displayed at full resolution.

FIG. 7 is a portion of a mammographic image that has been selected fordisplay at full resolution displayed at full resolution.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Embodiments of the invention will now be described with reference to theaccompanying figures, wherein like numerals refer to like elementsthroughout. The terminology used in the description presented herein isnot intended to be interpreted in any limited or restrictive manner,simply because it is being utilized in conjunction with a detaileddescription of certain specific embodiments of the invention.Furthermore, embodiments of the invention may include several novelfeatures, no single one of which is solely responsible for its desirableattributes or which is essential to practicing the inventions hereindescribed.

FIG. 1 is a block diagram of an exemplary computing system 100 incommunication with a network 160 and various network devices. Thecomputing system 100 may be used to implement certain systems andmethods described herein. The functionality provided for in thecomponents and modules of computing system 100 may be combined intofewer components and modules or further separated into additionalcomponents and modules.

The computing system 100 includes, for example, a personal computer thatis IBM, Macintosh, or Linux/Unix compatible. In one embodiment, theexemplary computing system 100 includes a central processing unit(“CPU”) 105, which may include a conventional microprocessor, anapplication module 145 that comprises one or more various applicationsthat may be executed by the CPU 105. The application module 145 mayinclude, by way of example, components, such as software components,object-oriented software components, class components and taskcomponents, processes, functions, attributes, procedures, subroutines,segments of program code, drivers, firmware, microcode, circuitry, data,databases, data structures, tables, arrays, and variables.

The computing system 100 further includes a memory 130, such as randomaccess memory (“RAM”) for temporary storage of information and a readonly memory (“ROM”) for permanent storage of information, and a massstorage device 120, such as a hard drive, diskette, or optical mediastorage device. Typically, the modules of the computing system 100 areconnected to the computer using a standards-based bus system. Indifferent embodiments of the present invention, the standards based bussystem could be Peripheral Component Interconnect (PCI), Microchannel,SCSI, Industrial Standard Architecture (ISA) and Extended ISA (EISA)architectures, for example.

The computing system 100 is generally controlled and coordinated byoperating system software, such as the Windows 95, 98, NT, 2000, XP orother compatible operating systems. In Macintosh systems, the operatingsystem may be any available operating system, such as MAC OS X. In otherembodiments, the computing system 100 may be controlled by a proprietaryoperating system. Conventional operating systems control and schedulecomputer processes for execution, perform memory management, providefile system, networking, and I/O services, and provide a user interface,such as a graphical user interface (“GUI”), among other things.

The exemplary computing system 100 includes one or more of commonlyavailable input/output (I/O) devices and interfaces 110, such as akeyboard, mouse, touchpad, and printer. In one embodiment, the I/Odevices and interfaces 110 include one or more display devices, such asa monitor, that allows the visual presentation of data to a user. Moreparticularly, display devices provide for the presentation of GUIs,application software data, and multimedia presentations, for example. Inone embodiment, a GUI includes one or more display panes in whichmedical images may be displayed. According to the systems and methodsdescribed below, medical images may be stored on the computing system100 or another device that is local or remote, displayed on a displaydevice, and manipulated by the application module 145. The computingsystem 100 may also include one or more multimedia devices 140, such asspeakers, video cards, graphics accelerators, and microphones, forexample.

In the embodiment of FIG. 1, the I/O devices and interfaces 110 providea communication interface to various external devices. In the embodimentof FIG. 1, the computing system 100 is coupled to a network 160, such asa LAN, WAN, or the Internet, for example, via a communication link 115.The network 160 may be coupled to various computing devices and/or otherelectronic devices. In the exemplary embodiment of FIG. 1, the network160 is coupled to imaging devices 170, an image server 180, and amedical facility 190. In addition to the devices that are illustrated inFIG. 1, the network 160 may communicate with other computing, imaging,and storage devices.

The imaging devices 170 may be any type of device that is capable ofacquiring medical images, such as an MRI, x-ray, mammography, or CT scansystems. The image server 180 includes a data store 182 that isconfigured to store images and data associated with images. In oneembodiment, the imaging devices 170 communicate with the image servervia the network 160 and image information is transmitted to the imageserver 160 and stored in the data store 182. In one embodiment, theimage data is stored in Digital Imaging and Communications in Medicine(“DICOM”) format. The complete DICOM specifications may be found on theNational Electrical Manufactures Association Website at<medical.nema.org>. Also, NEAM PS 3—Digital Imaging and Communicationsin Medicine, 2004 ed., Global Engineering Documents, Englewood Colo.,2004, provides an overview of the DICOM standard. Each of theabove-cited references is hereby incorporated by reference in theirentireties. In one embodiment, the data store 182 also stores theuser-defined display parameters associated with one or more of theimages stored on the data store 182. As discussed in further detailbelow, the user-defined display parameters may vary depending of thetype of image, area imaged, clinical indication, source of image,display device, user, or other factors. Accordingly, any type ofuser-defined display parameter is expressly contemplated for use inconjunction with the systems and methods described herein.

The exemplary image server 160 is configured to store images frommultiple sources and in multiple formats. For example, the image server160 may be configured to receive medical images in the DICOM format frommultiple sources, store these images in the data store 182, andselectively transmit medical images to requesting computing devices.

The medical facility 190 may be a hospital, clinic, doctor's office, orany other medical facility. The medical facility 190 may include one ormore imaging devices and may share medical images with the image server180 or other authorized computing devices. In one embodiment, multiplecomputing systems, such as the computing system 100 may be housed at amedical facility, such as medical facility 190.

Definition of Terms

Below is a definition of certain terms used herein.

“Medical image” is defined to include an image of an organism. It mayinclude but is not limited to a radiograph, computed tomography (CT),magnetic resonance imaging (MRI), Ultrasound (US), mammogram, positronemission tomography scan (PET), nuclear scan (NM), pathology, endoscopy,ophthalmology, or many other types of medical images. While thisdescription is directed to viewing and tracking of medical images, themethods and systems described herein may also be used in conjunctionwith non-medical images, such as, images of circuit boards, airplanewings, and satellite images, for example.

“Modality” is defined as a medical imaging device (a patient whoundergoes an MRI is said to have been examined with the MRI modality).

“Patient” refers to an individual who undergoes a medical imagingexamination.

“Viewing” is defined to include the process of visually observing one ormore medical images associated with exams.

“Viewer” is defined as any person who views a medical image.

“Reading” is defined to include the process of visually observing one ormore medical images for the purpose of creating a professional medicalreport, also called an interpretation. When reading is complete, an exammay be labeled “read,” indicating that the medical professional hascompleted observation of the one or more medical images for purposes ofcreating a medical report.

“Reader” is defined to include one who is authorized to perform thereading process.

“User” is defined to include any person that is a viewer and/or areader.

“Display parameters” are defined to include methods of display of animage or exam. For example, an image or exam may be displayed with acertain pixel window level or width (similar to brightness andcontrast), in color, based on a certain color map, opacity map, or otherdisplay parameters.

“Full pixel display” is defined to include display on a monitor or otherdisplay system of every pixel of a medical image.

“Full Resolution” is defined to include the concurrent display of allpixels of a medical image portion on a display device.

“Reduced Resolution” is defined to include display of less than all ofthe pixels of a medical image portion on a display device.

“User-defined display parameter” refers to rules that a user canestablish and store in a database that establish criteria for imagedisplay that is considered adequate. For example, a user-defined displayparameter might store a rule that triggers certain warnings or displaysif all pixels are not displayed or alternatively if at least half thepixels are not displayed, or alternatively, if some determined fractionof the pixels are not viewed with a certain display method (such asimage window, level, brightness, contrast, opacity, color look-up table,or other parameters). User-defined display parameters may also refer toother image processing functions, such as edge enhancement and automatedimage analysis functions, e.g., computer-aided detection (CAD)techniques

FIG. 2 is a flowchart illustrating a method of tracking which pixels ofa medical image have been displayed according to user-defined displayparameters. In one embodiment, the method described with respect to FIG.2 is performed by a computing system 100, a medical facility 190, or animage server 190, for example. For ease of description, the method willbe discussed below with reference to a computing system 100 performingthe method. Depending on the embodiment, certain of the blocks describedbelow may be removed, others may be added, and the sequence of theblocks may be altered.

In one embodiment, the user-defined display parameters specify that anentire medical image must be viewed at full resolution before a readermay mark the image as read. However, the user-defined display parametersmay have different requirements, such as requiring that at least adefined portion of the pixels are displayed at full resolution and/or adefined portion of the pixels are viewed with a certain display method,for example. In another embodiment, the user-defined display parametersmay specify that the medical image is viewed at a resolution that isless than full resolution. In other embodiments, the user-defineddisplay parameters may specify additional display settings that must besatisfied in order to allow the reader to mark the image as read. Forexample, the display parameters may be set to require that every n^(th)pixel is displayed. Thus, various user-defined display parameters may beestablished on a user, modality, or facility basis, for example. In oneembodiment, such as when viewing CT images, the display parametersspecify that the CT images must be viewed using a specified series ofdisplay parameters, such as lung windows, bone windows, and/or othertypes of windows, for example. In this embodiment, if the user forgetsto view the images separately using all the required display parameters,the CT images may be misinterpreted. For ease of description, thefollowing description refers to user-defined display parametersspecifying that every pixel of the image is displayed at full resolutionbefore it may be marked as read. However, the methods described hereinare not limited to these display parameters and application of thesemethods using other user-defined display parameters are expresslycontemplated. Any reference to tracking pixels at full resolution shouldbe interpreted to cover similar systems and methods for monitoringand/or tracking of any other user-defined display parameter orcombination of display parameters.

In some embodiments, it may be important and/or required that a userview all of a medical image at full resolution. Thus, a user may berequired to adjust the portion of the medical image that is displayed atfull resolution on the display device in an attempt to view all of theimage pixels. However, currently there are no systems or methods forautomatically tracking the portions of a medical image that have alreadybeen displayed at full resolution, or for indicating those images forwhich all pixels have been presented on a display device at fullresolution (“full pixel display”). Accordingly, there is a need forimage viewing devices and computing systems that monitor the portions ofthe medical image that are displayed on the display device, notate thoseportions that have been displayed at full resolution (or otheruser-defined display parameters), and provide the user with informationindicating portions that have not been viewed at full resolution and/orprovide information indicating for which images of a multiple imageexamination full pixel display has been accomplished. These processesare referred to herein as “visual pixel tracking.”

In one embodiment, visual pixel tracking applies to the display of anindividual image. In another embodiment, visual pixel tracking appliesto a volume rendering, wherein after 3-D slicing, the computing system100 indicates which pixels in a volume have not been displayed at fullresolution or meeting other user-defined display parameters. FIG. 2,described in detail below, is a flowchart illustrating an exemplarymethod of tracking which pixels of a medical image are displayedaccording to user-defined display parameters. When volume rendering isperformed, the method of FIG. 2 may be applied to each slice of theimaging volume. The user interface may provide a real time status ofviewing each of the slices at full resolution.

In one embodiment, the computing system 100 is configured to determine aportion of the medical image on which visual pixel tracking is to beapplied. Many medical images comprise areas surrounding the area ofinterest that are not important for a user, such as a doctor, to viewand mark as read. For example, a medical image of a breast typicallyincludes areas, such as air around the breast, that are irrelevant tothe analysis by the user. Accordingly, viewing of these irrelevantportions of the image according to the user-defined display parametersis not necessary. In one embodiment, the computing system 100 analyzesthe medical image and determines those areas that are irrelevant to theuser's analysis. These irrelevant areas are then excluded from theuser-defined display parameters and a viewer may mark an image as readwithout viewing the irrelevant areas at full resolution, for example. Inanother embodiment, the user may define the irrelevant areas of an imageprior to viewing portions of the image at full resolution. For example,the user may use the keyboard, mouse, or other input device, to selectareas surrounding the area of interest that do not require viewingaccording to the user-defined display parameters. In yet anotherembodiment, the user may determine that the relevant portions of animage have been viewed according to the display parameters, without theneed to pre-select portions that should be viewed according to thedisplay parameters. By providing for automatic and/or manual selectionof irrelevant portions of a medical image, the viewer is not required todisplay those irrelevant portions of the medical image according to theuser-defined display parameters, such as full resolution.

In a block 210, one or more medical images are received from an imagesource. Although the process described below is directed to processingone image, it is possible to use the process in conjunction withmultiple images. The image source may comprise one or more of theimaging devices 170, the image server 180, the medical facility 190, orany other device that is capable of transmitting medical images. Themedical image may be received via the network 160, or by other means,such as transferred on a floppy disk or CD-ROM. For ease of description,in the description that follows the exemplary computing system 100 willbe the device that receives and displays the medical image. However,other computing devices may perform the methods described herein. Thereceived medical image comprises more pixels that the display deviceand, thus, the entire image may not be concurrently displayed at fullresolution.

Continuing to a block 220, a portion of the medical image is selectedfor display on the display device. As discussed above, many medicalimages contain more pixels than are capable of being displayedconcurrently on a display device. Accordingly, the user of the medicalimage may select a portion of the image to display at full resolution onthe display device. Alternatively, the computing system 100 mayautomatically determine a portion of the image to display on the displaydevice. For example, in one embodiment the computing system 100 mayinitially display a top, left portion of received medical image firstand then proceed to display adjacent portions of the image in responseto an input from the user.

Moving to a block 230, the portion of the image that was selected fordisplay at full resolution is displayed on the display device. Moreparticularly, all of the image pixels for the selected portion of themedical image are concurrently displayed on the display device. In oneembodiment, depending on the resolution of the medical image and theresolution of the display device, about 1-25% of the image may beconcurrently displayed at full resolution on the display device.

Continuing to a block 240, an indication of the portion of the imagethat is displayed at full resolution is recorded. For example, if ⅛ ofthe total pixels of an image are displayed at full resolution, anindication of these pixels is recorded, such as by storing pixelinformation in a memory 130 of the computing system 100. Alternatively,the information regarding displayed pixels may be stored on a centralserver, such as the image server 180, which may then be accessible toother medical facilities and imaging devices.

In a decision block 250, the computing system 100 determines if anotherportion of the image has been selected for display at full resolution.In one embodiment, the user is presented with a reduced resolutionrepresentation of the medical image and is allowed to select anotherportion of the image for display at full resolution. Selection of animage portion may be accomplished by pressing certain keys on akeyboard, such as the arrow keys, for example. In another embodiment,the user may change the selected portion for viewing by moving a mouse,or other input device. For example, a pan tool may be invoked by theuser, allowing the user to adjust the portion of the image displayed atfull resolution so that areas of the images that are above, below, or tothe sides of the current displayed portion are displayed at fullresolution. In another embodiment, the computing system 100 may beconfigured to periodically updated the display with a portion of theimage that has not yet been displayed at full resolution, or update thedisplay in response to an input from the user.

If in the decision block 250, the computing device 100 determines thatinstructions have been received to display another portion of the imageon the display device, at a block 280 the requested portion of the imageis selected for display at full resolution. In one embodiment, such aswhen a panning tool is used, the selected portion comprises much of thecurrently displayed portion of the image. In another embodiment, theselected portion comprises a portion of the image that is entirelydifferent than the portion of the image that is currently displayed.

Moving to a block 290, one or more display characteristics of theselected portion of the image that is displayed at full resolution isaltered. Thus, when the entire image is displayed on the display deviceat a reduced resolution, those portions of the image that have not beendisplayed at full resolution can be identified. These portions of theimage may then be selected for display at full resolution.

In one embodiment, the adjustment of a display characteristic compriseschanging a color of the image portion. In another embodiment, otherindicators, such as a line surrounding those image portions alreadydisplayed at full resolution, may be used to discriminate betweenportions of the image that have been displayed at full resolution andportions that have not been displayed at full resolution. Accordingly,when the entire image is viewed at a reduced resolution, such as bydisplaying only every n^(th) image pixel, where n is less than or equalto the ratio of image pixels to display pixels, areas of the image thathave not been viewed at full resolution are distinguished from thosethat have been viewed at full resolution. Based on the distinguishingdisplay characteristic, the user may select for display a portion of theimage that has not yet been displayed at full resolution. In oneembodiment, coloring of the viewed pixels may be toggled on and off bythe user. In another embodiment, a text message, icon, or otherindication, may be displayed at the bottom of the display, for example,indicating that the image has been viewed according to the user-defineddisplay parameters. In yet another embodiment, the outside margins ofthe viewing pane may change color or the system could beep or providesome other audible feedback when the image has been displayed accordingto the user-defined display parameters.

Moving from block 290, the selected portion of the image is displayed atfull resolution in block 230, and the method continues to block 240 andblock 250. Accordingly, blocks 230, 240, 250, 280, and 290 may berepeated multiple times in the process of selecting and displayingportions of an image at full resolution.

Referring again to the decision block 250, if the computing device 100determines that instructions to display another portion of the image atfull resolution have not been received, the method continues to adecision block 260, wherein the computing device 100 determines whetherall of the image has been displayed at full resolution. If it isdetermined that not all of the image has been displayed at fullresolution, the method continues to a block 295, wherein an indicationis provided to the user that not all of the image has been viewed atfull resolution. If, however, in the decision block 260, the computingdevice 100 determines that the entire image has been displayed at fullresolution, the method continues to a block 270, wherein an indicationis provided to the user that the entire image has been displayed at fullresolution.

As noted above, the flowchart of FIG. 2 illustrates an exemplary processof tracking pixels viewed by a user according to exemplary user-defineddisplay parameters. In particular, the user-defined display parametersin the example of FIG. 2 specify that the entire image is viewed at fullresolution. However, in other embodiments the user-defined displayparameters may require that, for example, only a portion of the image isdisplayed at full resolution, or any other predetermined reducedresolution. For example, many images contain non-rectangular areas ofinterest. The portions outside of the areas of interest, such as abreast in a mammography image, may include air, other body portions, orimaging equipment, for example. Those of skill in the art will recognizethat is not important to analyze every pixel of the air surrounding anarea or interest. Accordingly, in one embodiment, the user or thesoftware may select portions of the image that must be displayedaccording to the user-defined display parameters. In another embodiment,the display parameters may specify that the viewer determines when theimage has been viewed according to the user-defined display parameters.In this embodiment, the system may track the viewed pixel of the image,present the viewer with a view of the image that distinguishes portionsof the image that have not been viewed at full resolution, or accordingto any other user-defined display parameters, and the viewer candetermine whether the image can be marked as read.

In one embodiment, the user can establish user-defined displayparameters and store those parameters in a database. For example, theuser may establish a rule linked to the individual user, user type, examtype, modality, system or other links that triggers the above describedautomatic warnings and/or visual pixel tracking if a user-definedfraction of the pixels are displayed. The user may, alternatively oradditionally, establish other rules linked to the individual user, usertype, exam type, modality, and/or system that trigger theabove-described automatic warnings and/or visual pixel tracking if animage is not viewed using one or more specified display parameters orcombination of display parameters. For example, the computing system 100may be configured to automatically direct the user to any pixels orimages that have not been displayed with specific display parameters.

In another embodiment, rules may be generated to automatically designatewhen the pixel tracking process should be turned on and off. Forexample, rules may designate that visual pixel tracking applies to onlycertain viewers or users. In one embodiment, one type of displayparameters can apply to one modality and another set of displayparameters can apply to another modality.

In one embodiment, the user is not able to notate an image as beingread, or completely viewed, until the entire image has been displayed atfull resolution. Accordingly, in the exemplary method of FIG. 2, if notall of the image has been displayed at full resolution, the methodindicates that the entire image has not been viewed at full resolutionin block 295, and the method returns to block 250, wherein anotherportion of the image may be selected for viewing.

In one embodiment, the computing system 100 automatically displaysportions of the image that have not yet been displayed at fullresolution, and/or that have not been displayed such that user-defineddisplay parameters have been met. For example, a user interface mayinclude visual indications as to which portions of an image includepixels that have not been displayed, or which pixels have not beendisplayed using a user-defined display parameter, such as a specifiedwindow or level setting. In one embodiment, the computing system 100automatically displays a message indicating which one or more of severalimages has not displayed with full pixel display and/or meetinguser-defined display parameter criteria. In another embodiment, thecomputing system 100 automatically directs the user to any imagepositions or images, that have not been displayed at full resolutionand/or meeting user-defined display parameter criteria.

FIG. 3 is an exemplary graphical user interface (GUI) 300 including amenu bar 320, multiple toolbars 310, and an image viewing pane 330. Inthe example of FIG. 3, a mammographic image is displayed in the viewingpane 330, wherein the entire image is displayed at a reduced resolution.For example, if the mammography image comprises 16 million pixels (e.g.,an image resolution of 4,000×4,000), all of the 16 million pixels cannotbe simultaneously displayed on a display device with a resolution of2,048×1,536 (a 3.2 Megapixel display). Thus, only about ⅕ of the 16million pixels of the mammography image may be displayed simultaneouslyat full resolution on such a display device. Accordingly, in order toview the entire mammographic image on a display device, the number ofpixels in the image is reduced by removing about 4 of every 5 pixels.Those of skill in the art will recognize that there are many systems andmethods for reducing the resolution of a digital image. These systemsand methods are contemplated for use in generating a reduced resolutionimage, such as the image displayed in the viewing pane 330 of FIG. 3.

As noted above, because many medical images, such as mammography images,for example, may include features or abnormalities that are onlydetectable by viewing only 1, or a few, pixels, a viewer of the image340 may not be able to detect all features and abnormalities.Importantly, the viewer of a mammographic image displayed at less thanfull resolution, such as image 340, may not be able to detect anabnormality related to breast cancer. For example, the area 350 shown inFIG. 3 may include many times more pixel than are displayed in the area350.

FIGS. 4 and 5 illustrate a method of sequentially viewing portions of amedical image at full resolution and related methods of tracking andindicating the portions of the image that have been viewed at fullresolution. In the embodiment of FIGS. 4 and 5, the reduced resolutionimage remains in the viewing pane 330 while a portion of the image isalso displayed at full resolution within the viewing pane 330.

FIG. 4 is the GUI 300 with the mammographic image 340 (FIG. 3) displayedin the viewing pane 330 at a reduced resolution, where a window 410displays a portion of the image at full resolution. In one embodiment,the portion of the mammographic image that is displayed at fullresolution in the window 410 is selected by the user, such as byallowing the user to move a cursor, or other icon, over portions of themammographic image. In this embodiment, when the cursor is over an areaof the mammographic image, the window 410 displays at full resolutionthe portion of the mammographic image currently covered by the cursor.Thus, in the example of FIG. 4, the window 410 display all of the pixelsof a portion of the reduced resolution image 340.

In one embodiment, the portion of the image displayed at full resolutionin the window 410 is updated as the user moves the cursor across thereduced resolution mammographic image 340. Thus, the user may determinethe order in which portions of the reduced resolution image are viewedat full resolution and may control the speed at which portions of theimage are viewed at full resolution.

FIG. 5 is the GUI 300 with the reduced resolution mammographic image 340(FIG. 3) displayed in the viewing pane 330, wherein portions of theimage that have been displayed at full resolution are distinguished fromportions of the image that have not yet been displayed at fullresolution. In the embodiment of FIG. 5, for example, the portions ofthe image that have already been viewed at full resolution, such as viathe window 410 (FIG. 4) are color inverted from those portions that havenot been viewed at full resolution. In FIG. 5, the non-inverted imageportion 510 indicates that this portion has been displayed at fullresolution. The inverted image portion 520, which substantiallysurrounds the non-inverted image portion 510, indicates that portion 520has not been viewed at full resolution. Accordingly, if the viewer isrequired to view all of the image at full resolution, the portion 520would need to be viewed at full resolution.

In another embodiment, the portions of the image that have been viewedat full resolution are distinguished from those portions that have notbeen viewed at full resolution in other manners. For example, in oneembodiment a border may be displayed around those portions of the image340 that have been displayed at full resolution. In another embodiment,the portion that has been viewed at full resolution is color-inverted.In another embodiment, the coloring of the portion that has been viewedat full resolution is adjusted, such as by adding a yellow tint to thatportion.

FIGS. 6 and 7 illustrate another method of sequentially viewing portionsof a reduced resolution medical image at full resolution and relatedmethods of tracking and indicating the portions of the image that havebeen viewed at full resolution.

FIG. 6 is the GUI 300 with the reduced resolution mammographic image 640displayed in the viewing pane 330, wherein a portion of the image hasalready been displayed at full resolution and another portion of theimage is selected for display at full resolution. More particularly, theinverted portion 610 of the image (shaped generally as two overlappingrectangles), indicates that portion 610 has already been displayed atfull resolution. As described above, other methods of indicatingportions of an image that have been viewed at full resolution may beused also.

In one embodiment, a portion of the mammographic image 640 is selectedfor display at full resolution. The portion that is selected is sized sothat the selected portion may be displayed at full resolution in theviewing pane 330. In FIG. 6, for example, the selection window 620 hasapproximately the same vertical to horizontal proportions as the viewingpane 330. In addition, the selection window 620 is sized so that aportion of the image covered by the selection window 620 substantiallyfills in the viewing pane 330 when displayed at full resolution.

In one embodiment, the viewer may move the selection window 620 to anyportion of the viewing pane 330, such as by moving a mouse or pressingdesignated keys on a keyboard. Once the selection window 620 is over aportion of the image that the user would like to view at fullresolution, the user selects the portion by pressing a button on themouse or pressing a designated key on the keyboard, for example. In oneembodiment, after selecting a portion for viewing at full resolution,the viewing pane 330 is updated to display the selected portion at fullresolution in the viewing pane 330. After viewing the selected portionat full resolution for a predetermined period of time or until the userindicates, the viewing pane 330 is updated with the reduced resolutionimage 330, updated with an indication of the portion of the image thatwas viewed at full resolution. Alternatively, the viewing pane 330 maybe sequentially filled with full resolution portions of the imagewithout returning to the reduced resolution image.

FIG. 7 is the GUI 300 with a portion of a mammographic displayed at fullresolution in the viewing pane 330. As noted above, many medical images,such as mammographic images, are taken at resolutions that are higherthan resolutions of typical display and, thus, all pixel of thesemedical images may not concurrently be displayed. As illustrated in FIG.7, a portion of a mammographic image is displayed at full resolution 710in the viewing pane 330 of the GUI 300. The portion of the imagedisplayed at full resolution in the viewing pane may be selected by theuser (such as is described with reference to FIG. 6) or may be selectedby the computing device according to predetermined display criteria.

In another embodiment, a viewing pane includes two panes, where a firstpane, or selection pane, displays the image at a reduced resolution anda second pane, or display pane, displays at least a portion of the imageat full resolution, or other user-defined display parameters. Forexample, a single display device could concurrently display an imagesuch as the mammographic image 640 in the selection pane and a selectedportion of the mammographic image 640 may be viewed in the display paneat full resolution, such as the full resolution image portion 710. Inone embodiment, the selection pane may be sized to correspond to thesize and shape that will accommodate a full resolution display pane. Inone embodiment, the user may be provided with at least two methods ofselecting portions of the reduced resolution image for viewing in thedisplay pane. In particular, the user may move a selection window, suchas the selection window 620 (FIG. 6), in the selection pane and thecorresponding image area may be updated in the display pane.Alternatively, the user may use a pan function in the display pane andthe position of the selection window in the selection pane isdynamically updated. In either case, areas that have been viewed at fullresolution, or according to other user-defined display parameters, aredynamically adjusted so that they may be distinguished from theremaining portions. In an embodiment incorporating a selection anddisplay pane, the relative sizes of the panes may be adjusted by theuser or, alternatively, may be automatically adjusted by the softwareaccording to predetermined criteria.

In yet another embodiment, the selection pane may include multiple panesthat each display a different image at a reduced resolution. Forexample, the multiple panes may display various images in a single imageseries. In one embodiment, the reduced resolution images are adjusted sothat portions of the images that have been viewed at full resolution, orother user-defined display parameters, are visually distinguishable fromthe remaining portions. Accordingly, the display may provide an overviewof the viewing status of multiple images.

The foregoing description details certain embodiments of the invention.It will be appreciated, however, that no matter how detailed theforegoing appears in text, the invention can be practiced in many ways.For example, the above-described pixel checking method may be performedon other types of images, in addition to medical images. For example,images of circuit boards, airplane wings, and satellite imagery may beanalyzed using the described systems and methods for monitoring whetheran image has been viewed according to predefined display parameters. Asis also stated above, it should be noted that the use of particularterminology when describing certain features or aspects of the inventionshould not be taken to imply that the terminology is being re-definedherein to be restricted to including any specific characteristics of thefeatures or aspects of the invention with which that terminology isassociated. The scope of the invention should therefore be construed inaccordance with the appended claims and any equivalents thereof.

1. A method of viewing medical images on a display device coupled to acomputing system, wherein the display device is configured toconcurrently display N pixels of an image to a user, the methodcomprising: (a) receiving an image at the computing system, wherein theimage comprises M pixels, wherein M is greater than N; (b) displaying onthe display device a portion of the image comprising N pixels, whereinthe image portion is displayed at full resolution; (c) determiningwhether each of the M pixels of the image has been displayed on thedisplay device; and (d) in response to determining that not all of the Mpixels of the image have been displayed on the display device, returningto step (b).
 2. The method of claim 1, wherein software executing on thecomputing system determines N, wherein N is less than a total number ofpixels of the display device.
 3. The method of claim 1, wherein N issubstantially equal to a total number of display pixels minus a numberof pixels that are used for display of other features.
 4. The method ofclaim 1, further comprising: displaying on the display device the entiremedical image at a reduced resolution; selecting a portion of thereduced resolution medical image for display at full resolution, whereinthe selected portion comprises no more than N pixels; and displaying theselected portion at full resolution, wherein the selected portion atfull resolution replaces the display of the entire medical image at thereduced resolution.
 5. The method of claim 1, wherein the userdetermines the image portion that is displayed on the display device. 6.The method of claim 1, wherein the computing system determines the imageportion that is displayed on the display device in response todetermining which of the M pixels have been displayed on the displaydevice.
 7. The method of claim 1, further comprising adjusting a displaycharacteristic of the image portion that is displayed on the displaydevice.
 8. The method of claim 7, wherein the display characteristic isa color of the image portion.
 9. The method of claim 8, wherein thecolor of each of the N pixels is inverted after each of the N pixels isfirst displayed on the display device.
 10. The method of claim 1,further comprising displaying indicia on the display device as a resultof determining that not all of the M pixels of the image have beendisplayed on the display device.
 11. A method of viewing a mammographicimage in a viewing pane depicted on a display device, wherein theviewing pane is configured to display a predetermined number of pixels,the method comprising: displaying the mammography image at a reducedresolution in the viewing pane; displaying a portion of the mammographicimage at full resolution in the viewing pane; displaying the mammographyimage at the reduced resolution in the viewing pane, wherein a portionof the reduced resolution image that corresponds with the portion of themammographic image that was displayed at full resolution is visuallydistinguishable from the remaining portion of the reduced resolutionimage.
 12. The method of claim 11, wherein a display characteristic ofthe portion of the mammographic image that was displayed at fullresolution is changed.
 13. The method of claim 11, wherein the reducedresolution image comprises in the range of about 1 to 50 percent of thepixels of the mammography image.
 14. The method of claim 11, whereindisplaying the portion of the mammographic image at full resolution inthe viewing pane comprises: replacing the display of the reducedresolution image with the portion of the mammographic image at fullresolution so that the portion of the image at full resolutionsubstantially fills the viewing pane.
 15. The method of claim 11,wherein displaying the portion of the mammographic image at fullresolution in the viewing pane comprises: depicting a window within theviewing pane; displaying in the window the portion of the mammographicimage at full resolution and concurrently displaying portions of thereduced resolution image outside of the window and within the viewingpane.
 16. The method of claim 15, wherein the full resolution portion ofthe mammographic image displayed in the window is changed in response touser commands via an input device, wherein the full resolution portiondisplayed in the window is updated in real time as the user commands arereceived.
 17. The method of claim 16, wherein the input device is amouse.
 18. The method of claim 16, wherein the window is displayedadjacent to the portion of the mammographic image displayed at thereduced resolution.
 19. The method of claim 15, wherein a position ofthe window changes is response to the user commands, covers the portionof the mammographic image displayed at the reduced resolution.
 20. Acomputing system for viewing a mammographic image, the systemcomprising: a display device depicting a viewing pane; means fordisplaying a portion of the mammographic image at full resolution in theviewing pane; and means for displaying the entire mammographic image atthe reduced resolution in the viewing pane, wherein the portion of themammographic image displayed at full resolution is visuallydistinguishable from the other portions of the reduced resolutionmammographic image.
 21. A computing system for viewing a medical image,the system comprising: a display device having a predetermined number ofpixels; an input interface configured to receive the medical image; anapplication module comprising software for initiating display of themedical image on the display device; and a processing unit configured toexecute the software, wherein, in a first mode, the software initiatesdisplay of the entire medical image at a reduced resolution on thedisplay device; in a second mode, the software initiates display of aportion of the medical image at full resolution on the display device;and, in a third mode, the software initiates display of the entiremedical image at the reduced resolution on the display device, wherein aportion of the reduced resolution medical image corresponding to theportion of the medical image displayed at full resolution is visuallydistinguishable from the remaining portions of the reduced resolutionmedical image.
 22. A method of viewing medical images, the methodcomprising: selectively viewing portions of an image; and verifying thatthe entire image has been viewed according to user-defined displayparameters.
 23. The method of claim 22, wherein the user-defined displayparameters specify that the entire image is display at full resolution.